Moon, Mercury, Milky Way

On Wednesday evening, 16 June, Mercury was still visible and accompanied by the crescent moon during twilight.

Mercury (circled) and the Moon.  Olympus 40-150mm f/4.

 

Mercury (center) 1:1 crop.  Olympus 40-150mm

Near midnight, long after the moon had set, I imaged the Milky Way with an OM 20mm f/1.4 lens.

3x3 median digital filter

 

Summer Triangle, 3x3 median digital filter

These are the same two scenes with a physical Hoya Sparkle-6 filter:

 

A more southerly view:

 The layers of green and purple airglow are mostly invisible to the unaided eye and simply present as a vague brightening toward the horizon.  When strong airglow is present the sky near the horizon is typically about 0.4 mpsas brighter than directly overhead.

Daytime occultation of Venus

 Yesterday at 12:52 pm MDT the waxing crescent Moon passed in front of the planet Venus.  The event was visible in full daylight.  I set up a 360mm f/6 scope on a ZWO AM3 mount and used the go-to function to find the Moon and Venus in the bright blue sky.

Venus moments before occultation

 

Occultation begins

Later that evening the crescent Moon and Venus neatly framed the Beehive Cluster (M44) over Bristol Head:
 

The Moon, M44, and Venus

Venus, Jupiter, Mercury

 Mercury reached its furthest elongation from the Sun yesterday.  Even so, it is a difficult planet to catch from this location between two mountain ridges.  There is only a short time between when it becomes dark enough to see Mercury and when it slips behind the mountain.  Last night this was at 9 pm.

 

Venus (top), Jupiter (middle), and Mercury (bottom)

These are two views, enlarged 2x, of Mercury dipping into the treeline:

 Near midnight on the same evening the sky brightness was measured at sqml=21.68 mpsas, a very good value.  The Milky Way was well positioned for photographs.

Sony A7iii + Laowa 15mm f/2

 A 3x3 median filter was applied to this image in post processing to suppress the faint stars and let the Milky Way stand out.

 

 

Milky Way roundup

 The new moon is today, 15 June.  There are only a couple days left before the waxing moon begins to wash out views of the Milky Way.  Here is a roundup of some images taken during the dark skies of the past week.

 

7Artisans 7.5mm f/2.8 fisheye.  3x3 median filter

Laowa 7.5mm f/2.  Sparkle-6 filter

Panasonic Leica 9mm f/1.7. Sparkle-6 filter

Panasonic Leica 12mm f/1.4, 3x3 median filter

Panasonic Leica 12mm f/1.4, Softon filter

Sony A7iii + Rokinon 135mm f/2 Nikon AE

Sony A7iii + Rokinon 135mm AE

Sony A7iii + Rokinon 135mm AE, 3x3 median filter

E-M5iii + Rokinon 135mm f/2

This last image shows the star Antares (on the left), and the two globular clusters NGC 6144 (middle) and M4 (right).

Some nearby stars

 The second, third, and fourth nearest star systems are currently visible (with optical aid) in the late evening after twilight.  They are: Barnard's Star (second), Wolf 359 (third), and Lalande 21185 (fourth).  The following table shows the particulars: 

Some nearby stars in the evening sky

Rank	Name	distance (ly)	magnitude
2	Barnard's Star	5.96	9.5
3	Wolf 359	7.86	13.4
4	Lalande 21185	8.30	7.5
11	Ross 128	11.01	11.1
30	Wolf 1061	13.43	10.1

A couple of other nearby stars are included in this table because they are currently positioned for viewing as well.  These five stars are all red dwarfs, and all of them are too faint to be seen with the unaided eye.  In case you are wondering, the fifth-nearest star system is Sirius, which is also the brightest star in the night sky, and currently not visible in the evening.

 Three of these stars are located in the western sky: 

Ross 128 (left), Wolf 359 (middle), Lalande 21185 (right)

The other two are located in the east, preceding the rising Milky Way:

Barnard's Star (left), Wolf 1061 (right)

 The two images above were obtained with an Olympus E-M1iii camera and Panasonic Leica 9mm f/1.7 lens with a Hoya Sparkle filter.

The next set of images of the individual stars were obtained with an Olympus E-M5iii camera and a Rokinon 135mm f/2 lens.

Barnard's Star (circled). Second closest star system.

Wolf 359 (circled). Third closest star system.

Lalande 21185 (circled). Fourth closest star system.

Ross 128 (circled). 11th.

Wolf 1061 (circled). 30th.

The globular star cluster M107 appears down and to the left of Wolf 1061.

Post conjunction

 Venus and Jupiter are slowly separating.  Last night they were 2.76° apart and Venus is now above Jupiter as they set.  

Venus (top) and Jupiter (below)

 

Three of Jupiter's moons are visible: Ganymede, Europa, and Callisto.

Europa (second from left) is actually the combined image of Europa and Io, which were very close together.  These images were all obtained with the Olympus 40-150mm f/4 lens.

 

 As twilight fades the giant globular cluster Omega Centauri is still visible low (very low) in the south.

 

  

 These two images were obtained with a Rokinon 135mm f/2 lens on an Olympus E-M5iii camera.

 

Omega Centauri is estimated to contain 10 million stars and has a diameter of about 170 ly. 

 

Monday conjunction

 Jupiter and Venus were separated by only 1.7° on Monday evening (08 June).  

Olympus E-M1iii + 40-150mm f/4 lens. 

 

Three of the four Galilean moons of Jupiter (lower left) are visible.  From left to right: Europa, Callisto, Ganymede.